Process of electrically welding metals.



G. R. STURDEVANT. PROCESS or ELEOTBIGALLY WELDING METALS.

APPLIOATIOI FILED APR. 1, 1909.

Patented Sept. '21, 1909 ..AE%C,

' wrms ssss My invention provides simple and con- 2O UNITED stares PATENT orricui. j

CHARLES R. STURDEVANT, or won'cnsrnn, massacnusnm'rs, assrsnon T0 AMERICAN STEEL & WIRE eomraur, or woncnsrna, massacnusu'rrs, A CORPORATION or NEW JERSEY.

vertical section on the line IIII of Fig. 1,

illustrating also in diagram the electrodes by which the electric current is supplied for heating the parts to be welded; and Fig. 3

venient means for electrically welding two pieces of metal. It has'been' designed by me particularly with reference to its use in welding of rail bonds to rails, which-present peculiar difliculties; but the invention has more general application andmay be used for welding parts of metal together for other purposes. a

The figures of-the drawing illustrate an. application of my invention for the welding together of two pieces of metal, A and B. The part-A may be the web of a steel rail, and the part B the copper terminal of a rail bond which is to be aflixed to therail. For the purpose of welding these parts I apply the part B in proximity to the part A with an interposed insulating separator C, which is composed of a fusible fluxiug material or salt, which holds the parts A and B apart, presenting an intermediate space or pocket D open at the top. As shown in- Fig. 2 the insulating separator G is made of a separate piece and forms an open frame, which is set between the parts A and B; and when these parts have been so arranged the intervening space D is filled with a fused flux of a less melting point than the insulating material 0.; This fused flux may be of the composition such as has beenused heretofore 1 for the purpose of furnishing an electrolytic conductor for heating metals tobe joined together, by passing a current through a body of such flux and then displacing it with molten metal. Such flux commonly consists of a-mixture of borax, chlorates and carbonrnocuss or EpEcTmcALLY WELDING METALS.

specification f Ltters Patent Patented Sept. 21, 1909. Application filed April 1, 1909, Serial No. 487,2 34.

ates which have the property of melting readily and of affording a, convenient electrolytic conductor.

formity to the welding temperature which is to be attained. The body of insulating material C is also a fusible salt, but is The com osition and the pro ortions of the in redients will be modjifie' by those skilled m the art in conchosen so as to be of ahigher melting point than the molten material which is introduced into the space E. A suitable composition for this body of insulating material may be composed of substantially equal parts of borax I and silica, but other suitable materials may be used.

The space or pocketD having been charged with the molten salt, an electric current of large volume is supplied through the electrodes E and F of an electric welding machine. It flows through the metal pieces A and B. andthrough the intermediate body of fused electrolyte, which opposes considerable resistance and generates locally a high heat. It also has the function of cleansin the opposite surfaces of the metal parts.

- hen the metal parts A and B have been heated by the passage of the electric currentin this manner to the desired temperature to efiect their welding, the heat thus generated melts the body of insulating material C (the fusing temperature of which is substantially the same as the welding temperatures of the metals), and this body' thereupon drops away, causin the molten charge of flux to be discharge from the pocket D and immediately the metal pieces A and B are brought into contact, pressure is applied to them through the electrodes E and F by ,means of screws or levers usual in electric welding gether into intimate welding contact.

The advantages of this invention will be appreciated by those skilled in the art. Only those portions of the metal pieces A and B are heated which are desired to be welded, and the insulating material melts and dischar es at the critical period and serves as a reliafile index of the moment when the. surfaces have been suiiiciently heated and the welding pressure should be ap lied.

In Flg. 3 i show -a,modifie arrangement in which the body of insulating material C is not molded separately, as in Fig. 2, but is apparatus, and they are pressed toapplied as a glassy lining to the edge of the in insulatin piece B, and forqthisj-jjbitlgp ibse it may be applied bydipp'ing. the edge of said iece in the body of the molten material which will immediately chill and adhere. The sharp edge of the metal plate C being of copper, will melt away during the welding of the metals.

My invention may be applied to use in many ways, since What 1 claim is:

1. The method herein described of heating metal surfaces to be united, which consists the surfaces by fusible insulating materia placing an intermediate body of fusible material between the surfaces, and passing a current through the intermediate body until the insulating material has melted.

2. The method herein described of weldingmetal surfaces to be united, which consists in separating the surfaces by insulating material, placing a fusible flux between such surfaces having a lower meltin point than the fusible insulating materia, passing a current through the intermediate flux until metal surfaces, which consists in insulating p the surfaces from each other by a fusible 1nsulating material, and placing a body of fusible fluxing salt, having a lower fusing point than the insulating material, between the surfaces, and passing a current through the body of fluxing salt until the insulating material has melted; substantially as de scribed.

In testimony whereof, I have hereunto set my hand.

CHARLES R. STURDEVANT. Witnesses:

THOMAS W. BAKEWELL, EUGENE H. MURPHY. 

